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ProPublica Editor-in-Chief Stephen Engelberg says the website had good intentions in 2013 when it unveiled Prescriber Checkup, a database showing the prescribing habits of doctors from around the United States, revealing those who have a heavy hand. However, a recent check of its Google Analytics data showed that readers were using it in an unexpected way. Although health care professionals and law enforcement have benefited from this data, patients are also using it to find doctors who will overprescribe them opioid prescription painkillers.

“We recognize that it’s important not to ignore the not-so-beneficial uses of Prescriber Checkup,” Engelberg wrote on the website. “As one way of doing this, we are adding a warning to the pages of all narcotic drugs that reminds readers of the serious health risks posed by taking opioids for pain relief. We will also link to advice on their use by the Centers for Disease Control and Prevention and have written a story on the growing public health crisis arising from the abuse (of) prescription pain medication.”

Prescriber Checkup uses data from Medicare Part D to show the prescribing habits of doctors all over the United States. The purpose of this nationwide database was simple: provide a monitoring system that doctors, patients, hospital administrators, and law enforcement could use to reveal which doctors are prescribing dangerously high doses of widely abused drugs. The Centers for Medicare and Medicaid Services offers a similar list on its website.

Engelberg noted the database has also been a useful way for doctors to compare their practices to those of their peers, for administrators to make sure their doctors are following best treatment practices, for law enforcement to check on leads for fraud and illicit trafficking of pain medication, and for patients to ensure that their doctors have a sound background.

Web data showed that an overwhelming number of visitors to Prescriber Checkup landed on the site after conducting searches like “doctors who prescribe narcotics easily’’ or “doctors that will prescribe anything.’’ Other patients used what Engelberg called a reporting recipe that was designed to help journalists find doctors who overprescribe. This year around 25 percent of page views were associated with narcotic painkillers, antianxiety medications, and amphetamines.

Opioid painkillers have become so widespread that as many as 259 million prescriptions were written in 2012, which is enough for every American adult to have a bottle of pills. Researchers from Stanford University Medical Center recently investigated Medicare prescription drug claims that were made in 2013 to count the number of doctors overprescribing opioids.

That year, 15.3 million prescriptions were written in family practice, 12.8 million in internal medicine, 4.1 million by nurse practitioners, and 3.1 million by physician’s assistants. The most active 10 percent of them accounted for 57 percent of prescriptions. The results of this study refuted claims that the majority of unnecessary prescriptions come from so-called pill mills, unlicensed clinics that dispense prescription opioids without a medical exam.